I've been thinking long and hard about the relative advantages of each. Both types are of course very good exercises when you look at it, but believe it or not they have different effects on your body. Let's start with endurance running. If you've ever tried to run for 30 minutes straight you know that it's primary an aerobic workout. Your heart is at an overall faster pace and your lung get a pretty good workout as well. Endurance runners tend to have lean muscles because this type of running doesn't exactly promote the kind of muscle growth that weight lifting does. It primarily supports the lean muscles. Next is Sprinting. It's an explosive exercise and it really gets the heart going. It also trains the fast twitch muscles but doesn't really train your endurance. Your lungs don't get the same workout. Endurance is very important if you are into a lot of sports. So in your opinion, what's better?